This study seeks to extend previous observations of increased energy expenditure during long term hypercortisolemia states by addressing the hypothesis that an associated lipolysis is a principal mechanism for this response. Healthy subjects will be evaluated under cortisol associated hyperinsulinemia or euinsulinemia conditions by 2 separate infusion studies of overnight duration. This study will also seek to determine if any residual effect of hypercortisolemia status persists in these subjects.